I've never had to mess with proportioning valves so I just want to confirm that I'm picturing this correctly.
I'm starting to piece things together for my brake system and have a simple question. With a proportioning valve like this: http://www.summitracing.com/parts/wi...0922/overview/ with a single inlet and a single outlet, would I just put it inline with the rear brake line so that I can dial it down if the rear brakes are too strong compared to the front? I considered trying it without a prop valve, but for $40 I don't see why not to use that if it's as simple as I picture.

In case it matters, here's the setup I'm gonna be running: 1998 TJ with late 70s Ford Dana 60 axles. Stock vacuum booster, late 90s Dodge master cylinder(bigger bore than stock for the bigger brakes). All 4 corners will have the commonly used 1 ton Chevy single piston calipers and rotors. All 3/16" lines, single circuit to the front and single to the rear.

These are what we are running. Don't recall them being that expensive. We went with them figuring they wouldn't have issues with brake fluid like we might have if we went with a home depot plumbing aisle setup.

Sounds like Johnny has the same set-up as what is in my black Chevy.... I have the same shut off valve with a very similar proportioning valve from Summit. I've only had a few braking trials but feel its almost tuned - very easy.

I use the same proportioning valve on the rear line, ball valve from stinky fab(before I knew he nailed his former friends wife) inline with the rears mounted on the left side of the drivers seat so I can set the parking brake in the vehicle and the bigger dodge 90's master on a TJ booster. No braking complaints here.

I ran my jeep initially without a prop valve (I just gutted the stock jeep prop valve block allowing full flow) you will not like it. I have 1 ton disk brakes both ends. I added a simple prop valve, easy to tune. Works just like you are thinking.

My first try was two Biondo line locks and a Wilwood reducer in early 2002. I later went to four Biondo line locks and a Wilwood reducer (~2004?). I added the second pair of line locks so I could cut off flow to the bad brakes in event of a brake line failure after I had a cheap Autozone hose blow but the combination valve worked. I never did use the second pair because every time I blew a line the combination valve worked like it's supposed to.

I tried the emergency brake master cylinder idea run to my rear brakes. I used a small master cylinder, maybe it was from a Corvair or VW or Luv or something. I forget. My Dad had it in the garage. It was one of the more stupid things I did. I added a lot of brake line and hose to a system since the body moved separate from the chassis. Felt like I had a nerf ball under the brake pedal. I think I had it plumbed in for maybe 3 weeks. I removed it and the emergency brake pedal altogether.

Line locks are worth their weight in nuisance when it comes time to winch someone else. Takes a lot of strain off the drive train. Plus it's funny when someone tries to tow your vehicle.

My first try was two Biondo line locks and a Wilwood reducer in early 2002. I later went to four Biondo line locks and a Wilwood reducer (~2004?). I added the second pair of line locks so I could cut off flow to the bad brakes in event of a brake line failure after I had a cheap Autozone hose blow but the combination valve worked. I never did use the second pair because every time I blew a line the combination valve worked like it's supposed to.

I tried the emergency brake master cylinder idea run to my rear brakes. I used a small master cylinder, maybe it was from a Corvair or VW or Luv or something. I forget. My Dad had it in the garage. It was one of the more stupid things I did. I added a lot of brake line and hose to a system since the body moved separate from the chassis. Felt like I had a nerf ball under the brake pedal. I think I had it plumbed in for maybe 3 weeks. I removed it and the emergency brake pedal altogether.

Line locks are worth their weight in nuisance when it comes time to winch someone else. Takes a lot of strain off the drive train. Plus it's funny when someone tries to tow your vehicle.

The mud truck just has two line locks and a wilwood reducer.

I don't see the setup I'm running being an issue at all. It's this bracket: http://undercoverfab.com/brackets-an...acket-kit.html
And this master cylinder:http://www.summitracing.com/parts/wi...6089/overview/
It'll only require 2.5' or so of extra brake line, which on a Wrangler still makes the system shorter than most other vehicles. I don't see why it'd make it spongy, when not in use the pressure will just flow as normal, there is just a small reservoir inside the master instead of continuous brake line. As long as there's not a big ass air pocket or a bad seal then it should be invisible if I don't pull the lever. The body and cage are getting hardmounted to the frame so movement between them will be little to none.
If it doesn't work I'll get rid of it, but I'm confident enough in the idea that I've already got the parts on the way. Guess we'll find out.